Black Friday on 27 November: Test-Achats scrutinises discounts, check your crossed-out prices

Black Friday falls on 27 November 2026 and its week starts on 23 November, according to the guide Test-Achats published on 2 November. The consumer organisation notes that it is easy to advertise discounts of up to 50% on products whose price has already dropped. For a Belgian business selling online, every percentage on display will be read, compared and sometimes challenged.

1. What Test-Achats published on 2 November

According to Test-Achats, Black Friday week starts on Monday 23 November 2026 and discounts can run until Cyber Monday. The organisation says it has tested more than 200 online shops. Its "Un bon deal" tool assesses the quality of a product and its price against the previous 12 months.

L'Avenir relayed this advice the same day. According to Test-Achats, the paper also cites fewer than 25% of offers being genuinely worthwhile, a figure from an older study. Cyberwal by Digital Wallonia warns about fake promotions on smartphones, televisions and travel.

2. The Belgian reference price rule

Since the law of 8 May 2022, Article VI.18 of the Code of Economic Law governs how a price reduction is announced. According to Lexgo, the reference price is the lowest price the business applied in the 30 days immediately before the reduction. Test-Achats states the same principle.

Lexgo lists exceptions. For a product on the market for less than 30 days, the reference is the lowest price of the previous 7 days. For progressive reductions over 30 days at most, the same reference can be used. A reduction on day 31 needs a new reference.

3. What this changes for your campaigns

The percentage shown in an ad, a visual or a product page must stand up to this calculation. A "-50%" that the reference price does not support exposes the business, and consumers have tools to compare. This is our reading: the rule applies to every channel, not only the website.

One calendar point follows from the rule. For a first discount on 23 November, the 30-day window runs from 24 October to 22 November, by calculation. Any price cut decided before then lowers the reference.

4. Getting ready for the week of 23 November

Fix the list of products on promotion now, with their lowest price over 30 days. Calculate the percentages from that price, and only then write the messages. Have edge cases, such as recent products or progressive discounts, checked by your legal adviser.

The AI lens, humans first

AI can compare the price history of an entire catalogue in minutes, flag products whose planned percentage exceeds what the reference price allows, and produce ad copy variants once the figures are approved. It does not decide the discount level, the risky wording or how the law applies to a borderline case. Those choices stay human. AI executes. Expertise decides, and keeps watch.